A Novel Dynamic Voltage Influencing Metric for Cost-effective Voltage Control in Unbalanced Distribution Systems

The increased integration of distributed energy resources (DERs) and electric vehicles (EVs) in power distribution systems brings both opportunities and technical challenges. High penetration levels of DERs and random EV charging behaviors may cause additional voltage violations that are difficult to handle with classical voltage regulation devices. Fortunately, advances in power electronics facilitates using inverter-based DERs to provide reactive power support alongside existing regulation devices. Yet, controlling large number of inverter-based DERs can be challenging due to the increased communication requirements and control cost. This paper proposes a new dynamic system voltage influencer (SVI) paradigm that identifies the most suitable inverter-based DER assets that must be engaged in the voltage control program. SVI nodes are based on existing system topology and temporal changes in local load, DER, or EV patterns. Therefore, the proposed approach ranks the SVI nodes and uses the most influential nodes for voltage control applications. The proposed approach is verified via simulations on the IEEE 37 node test system. In addition to eliminating voltage violations, results show that it is possible reduce the cumulative control cost using the proposed dynamic SVI approach.